One known technique of building a bridge consists in prefabricating unit transverse bridge sections, and in placing these sections in situ by means of a launching girder, the set of sections composing a span being cantilevered out until it is integrated in the final structure.
This construction technique was used in particular to build the Bubiyan bridge in Kuwait (see PCI Journal of prestressed concrete institute January/February 1983, vol 28 no. 1, pp. 68-107) with a cantilevered length of about 40 m, which is a considerable achievement.
The technique of cantilevered placement enables shorter placement cycles to be obtained than are possible with any other known technique, however, it is rapidly limited by the weight of the cantilevered assembly, since excessive weight would lead to a launching girder whose size, weight and cost would be exorbitant.
Preferred embodiments of the present invention enable a bridge to be built by means of this technique with a cantilevered length that may be as much as 200 meters (m), but without requiring an exorbitant launching girder.